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#include <cassert>
#include <cstdio>

typedef long long LL;

const int MAXN = 300000 + 1;
const int MOD = 1000000007;

int n;
int a[MAXN];

LL sum[MAXN];
LL dp[MAXN];

LL do_real() {
    for (int i = 0; i <= n; i++) {
        sum[i] = 0;
        dp[i] = 0;
    }

    dp[0] = 1;

    for (int i = 1; i <= n; i++) {
        for (int j = 0; j < i; j++) {
            sum[j] = (sum[j] + a[i]) % MOD;
        }

        for (int j = 0; j < i; j++) {
            if (sum[j] % 2 == 0) {
                dp[i] = (dp[i] + dp[j]) % MOD;
            }
        }
    }

    return dp[n];
}

LL dp2[MAXN][2];

LL do_small() {
    dp2[1][0] = 1 - (a[1] % 2);
    dp2[1][1] = a[1] % 2;

    for (int i = 2; i <= n; i++) {
        if (a[i] % 2 == 1) {
            dp2[i][0] = dp2[i - 1][1];
            dp2[i][1] = 2 * dp2[i - 1][0];
        } else {
            dp2[i][0] = 2 * dp2[i - 1][0];
            dp2[i][1] = dp2[i - 1][1];
        }
    }

    return dp2[n][0];
}

int main() {
    scanf("%d", &n);

    LL sum = 0;
    bool small = true;
    for (int i = 1; i <= n; i++) {
        scanf("%d", &a[i]);
        sum += a[i];
        if (sum >= MOD) small = false;
    }
    printf("%lld\n", small ? do_small() : do_real());
}